diff --git a/src/unix/fs.c b/src/unix/fs.c
index eb17fb4a..362c36c6 100644
--- a/src/unix/fs.c
+++ b/src/unix/fs.c
@@ -946,6 +946,71 @@ static int uv__is_buggy_cephfs(int fd) {
 
   return uv__kernel_version() < /* 4.20.0 */ 0x041400;
 }
+
+
+static int uv__is_cifs_or_smb(int fd) {
+  struct statfs s;
+
+  if (-1 == fstatfs(fd, &s))
+    return 0;
+
+  switch ((unsigned) s.f_type) {
+  case 0x0000517Bu:  /* SMB */
+  case 0xFE534D42u:  /* SMB2 */
+  case 0xFF534D42u:  /* CIFS */
+    return 1;
+  }
+
+  return 0;
+}
+
+
+static ssize_t uv__fs_try_copy_file_range(int in_fd, off_t* off,
+                                          int out_fd, size_t len) {
+  static int no_copy_file_range_support;
+  ssize_t r;
+
+  if (uv__load_relaxed(&no_copy_file_range_support)) {
+    errno = ENOSYS;
+    return -1;
+  }
+
+  r = uv__fs_copy_file_range(in_fd, off, out_fd, NULL, len, 0);
+
+  if (r != -1)
+    return r;
+
+  switch (errno) {
+  case EACCES:
+    /* Pre-4.20 kernels have a bug where CephFS uses the RADOS
+     * copy-from command when it shouldn't.
+     */
+    if (uv__is_buggy_cephfs(in_fd))
+      errno = ENOSYS;  /* Use fallback. */
+    break;
+  case ENOSYS:
+    uv__store_relaxed(&no_copy_file_range_support, 1);
+    break;
+  case EPERM:
+    /* It's been reported that CIFS spuriously fails.
+     * Consider it a transient error.
+     */
+    if (uv__is_cifs_or_smb(out_fd))
+      errno = ENOSYS;  /* Use fallback. */
+    break;
+  case ENOTSUP:
+  case EXDEV:
+    /* ENOTSUP - it could work on another file system type.
+     * EXDEV - it will not work when in_fd and out_fd are not on the same
+     *         mounted filesystem (pre Linux 5.3)
+     */
+    errno = ENOSYS;  /* Use fallback. */
+    break;
+  }
+
+  return -1;
+}
+
 #endif  /* __linux__ */
 
 
@@ -960,40 +1025,21 @@ static ssize_t uv__fs_sendfile(uv_fs_t* req) {
   {
     off_t off;
     ssize_t r;
+    size_t len;
+    int try_sendfile;
 
     off = req->off;
+    len = req->bufsml[0].len;
+    try_sendfile = 1;
 
 #ifdef __linux__
-    {
-      static int no_copy_file_range_support;
-
-      if (uv__load_relaxed(&no_copy_file_range_support) == 0) {
-        r = uv__fs_copy_file_range(in_fd, &off, out_fd, NULL, req->bufsml[0].len, 0);
-
-        if (r == -1 && errno == ENOSYS) {
-          /* ENOSYS - it will never work */
-          errno = 0;
-          uv__store_relaxed(&no_copy_file_range_support, 1);
-        } else if (r == -1 && errno == EACCES && uv__is_buggy_cephfs(in_fd)) {
-          /* EACCES - pre-4.20 kernels have a bug where CephFS uses the RADOS
-                      copy-from command when it shouldn't */
-          errno = 0;
-          uv__store_relaxed(&no_copy_file_range_support, 1);
-        } else if (r == -1 && (errno == ENOTSUP || errno == EXDEV)) {
-          /* ENOTSUP - it could work on another file system type */
-          /* EXDEV - it will not work when in_fd and out_fd are not on the same
-                     mounted filesystem (pre Linux 5.3) */
-          errno = 0;
-        } else {
-          goto ok;
-        }
-      }
-    }
+    r = uv__fs_try_copy_file_range(in_fd, &off, out_fd, len);
+    try_sendfile = (r == -1 && errno == ENOSYS);
 #endif
 
-    r = sendfile(out_fd, in_fd, &off, req->bufsml[0].len);
+    if (try_sendfile)
+      r = sendfile(out_fd, in_fd, &off, len);
 
-ok:
     /* sendfile() on SunOS returns EINVAL if the target fd is not a socket but
      * it still writes out data. Fortunately, we can detect it by checking if
      * the offset has been updated.
@@ -1277,22 +1323,15 @@ static ssize_t uv__fs_copyfile(uv_fs_t* req) {
   if (fchmod(dstfd, src_statsbuf.st_mode) == -1) {
     err = UV__ERR(errno);
 #ifdef __linux__
+    /* fchmod() on CIFS shares always fails with EPERM unless the share is
+     * mounted with "noperm". As fchmod() is a meaningless operation on such
+     * shares anyway, detect that condition and squelch the error.
+     */
     if (err != UV_EPERM)
       goto out;
 
-    {
-      struct statfs s;
-
-      /* fchmod() on CIFS shares always fails with EPERM unless the share is
-       * mounted with "noperm". As fchmod() is a meaningless operation on such
-       * shares anyway, detect that condition and squelch the error.
-       */
-      if (fstatfs(dstfd, &s) == -1)
-        goto out;
-
-      if ((unsigned) s.f_type != /* CIFS */ 0xFF534D42u)
-        goto out;
-    }
+    if (!uv__is_cifs_or_smb(dstfd))
+      goto out;
 
     err = 0;
 #else  /* !__linux__ */